<!DOCTYPE html>
<html>
<head>
	<title>cache pic</title>
</head>
<script type="text/javascript">
	new Image().src = "images/a1.png";
	var mu0 = null;
	window.onload = function(){
		mu0 = new Audio("music/1.mp3");
		mu0.play();
		document.onclick = function(){
			mu0.pause();
		}
	}
</script>
<style type="text/css">
	#mu{
		display: block;
	}
</style>
<body>
<h1>Cache Image</h1>
<img id="pic" src="images/a0.png" alt="apple pic">
<script type="text/javascript">
	pic.onmouseover = function(){
		this.src="images/a1.png";
	}
	pic.onmouseout = function(){
		this.src="images/a0.png"
	}
</script>
<audio id="mu" src="music/1.mp3" controls="controls">
	你的浏览器不支持audio元素
</audio>
</body>
</html>